(1) Field of the Invention
The present invention relates to a thermoplastic resin composition having excellent mechanical toughness, heat resistance, electrical properties, moldability, chemical resistance, impact resistance and appearance of molded articles made therefrom, and a method for preparing the same. This composition of the present case can be widely utilized as materials for electrical and electronic parts, machine parts, automobile parts and the like.
(2) Description of the Prior Art
In recent years, with regard to engineering plastics, various new functions are additionally demanded, and various attempts have been made. One of them is a composition comprising a combination of plural engineering plastics, and this composition has features of the respective plastics and is known as a polymer alloy.
A polyphenylene ether resin is excellent in heat resistance, moldability and mechanical strength, but it has the drawback that its physical properties are somewhat poor. In consequence, the range of its uses is limited at times. On the other hand, a polycarbonate resin has excellent heat resistance, physical properties at low temperatures and impact resistance, but it is poor in chemical resistance and moldability and further has the disadvantage that stress cracks tend to occur therein. Furthermore, a polyoxymethylene resin is excellent in electrical properties but is poor in impact resistance. In particular, it can be presumed that materials having excellent heat resistance and impact resistance will become more and more important, and if the above-mentioned drawbacks of the polyphenylene ether resin and the other resins can be eliminated, they will become extremely useful materials. However, compositions of the polyphenylene ether resin and a polyamide resin or aromatic polyester resin are known, but there have not been compositions in which the polycarbonate resin and polyoxymethylene resin or another resin are used.
This reason is that these resins cannot be mixed easily with each other, since the chemical structures of the resins are different, and affinity between the resins is insufficient.